Process for dyeing aromatic polyamide fibers

ABSTRACT

AROMATIC POLYAMIDE FIBERS WHICH ARE HARDLY DYEABLE WITH COMMERCIAL DYES SUCH AS ACID DYES, METAL COMPLEX DYES, DIRECT DYES AND THE LIKE CAN READILY BE DYED WITH SUCH DYES TO GIVE A DEEP COLORED DYED PRODUCT BY TREATING THE FIBERS IN A BATH CONTAINING AS AN ACCELERATOR ONE OR MORE OF ALKYLBENZENE AND ALKYLNAPHTHALENE WHERE AT LEAST ONE HYDROGEN ATOM OF THE ALKYL MOIETY IS SUBSTITUTED WITH HALOGEN, OR DERIVATIVES THEREOF IN WHICH THE AROMATIC RING OF SAID COMPOUNDS IS SUBSTITUTED BY AN ALKYL GROUP OR A HALOGEN ATOM. THE ACCELERATOR MAY BE APPLIED BEFORE OR DURING DYEING. THE AMOUNT OF ACCELERATOR USED IN THE TREATING BATH IS 3 TO 30 G./LITER.

United States Patent Oifice 3,591,327 Patented July 6, 1971 Int. Cl. Dtl6p /00 US. Cl. 8166 11 Claims ABSTRACT OF THE DISCLOSURE Aromatic polyamide fibers which are hardly dyeable with commercial dyes such as acid dyes, metal complex dyes, direct dyes and the like can readily be dyed with such dyes to give a deep colored dyed product by treating the fibers in a bath containing as an accelerator one or more of alkylbenzene and alkylnaphthalene where at least one hydrogen atom of the alkyl moiety is substituted with halogen, or derivatives thereof in which the aromatic ring of said compounds is substituted by an alkyl group or a halogen atom. The accelerator may be applied before or during dyeing. The amount of accelerator used in the treating bath is 3 to 30 g./ liter.

The present invention relates to a process for efiiciently dyeing hardly dyeable polyamide fibers consisting of aromatic compounds.

Similarly to aliphatic polyamide fibers, for instance, such as nylon 6 and nylon 6.6, aromatic polyamide have a dye seat for anion dyes such as acid dyes, metal complex dyes, direct dyes and the like, however aromatic polyamide fiber cannot be dyed in deep shade with such dyes according to ordinary dyeing method. This is considered to be ascribable to the fact that because physical structure of said fibers (for example, polyhexamethylene terep'hthalamide fibers) is compact in physical structure and second order transition point of said fibers is very high (about 180 (2.), compared with those of nylon 6 and nylon 6.6, kinetic behavior of fiber molecules cannot be incurred actively, or that because structure of said fibers is compact from physical point of view, dye molecules cannot sufficiently be diffused into the inside of the fibers.

That is, hardly dyeable aromatic polyamide fibers cannot suificiently be dyed by a conventionally known method in which aliphatic polyamide fibers, for instance, such as nylon 6 and nylon 6.6 are dyed with acid dyes, metal complex dyes and direct dyes, or conventionally known method, i.e. so-called high temperature and high pressure dyeing method, in which hardly dyeable polyester fibers are efiiciently dyed with disperse dyes. Furthermore, said aromatic polyamide fibers cannot be dyed to give a sufficiently dyed product by such a dyeing method, wherein organic compounds, for instance, such as methylsalicylic acid, methylnaphthalene, chlorobenzene, orthophenylphenol and the like as an accelerator. As an accelerator used in dyeing said fibers with acid dyes, metacresol and paracresol have been reported in Textile Research Journal, vol. 35, pp. 999-1008, Aromatic polyamide fiber. This method, however, is not found to be satisfactory therefor.

As a result of extensive studies in methods of dyeing hardly dyeable aromatic polyamide fibers, the present inventors have succeeded in dyeing said fibers with acid dyes, metal complex dyes, direct dyes and the like to give a sufficient deep colored dyed product. The fibers are treated with one or more of alkylbenzene or alkylnaphthalene whose one or more of hydrogen atoms of the alkyl moiety is substituted with halogen, or alkylor halogen-nuclear substituted derivatives thereof.

Alkylbenzene and alkylnaphthalene whose one or more of hydrogen atoms of the alkyl moiety is substituted with halogen, and alkylor halogen-nuclear substituted derivatives thereof as used in the present invention include benzylchloride, benzylbromide, benzalc'hloride, benzalbromide, benzotrichloride, benzotribromide, a-ChlOIO- ethylbenzene, B-chloroethylbenzene, a-brornoethylbenzene, B-bromoethylbenzene, oor mor p-methylbenzylchloride, 0-, or mor p-chlorobenzyldichloride, o-, or mor p-bromobenzylchloride, o-, or mor p-methylbenzylchloride, o-, or mor p-chlorobenzylbromide, o-, or mor p-bromobenzylbromide, 1- or 2-(chloromethyl)-naphthalene, 2 (dichloromethyl) naphthalene, 1 (fit-chloroethyl)-naphtha1ene, lor 2-(bromoethyl)-naphthalene, l-(a-bromomethyl)-naphthalene, lor Z-(fl-bromoethyD- naphthalene, 2-methyl-1-(chloromethyl)-naphthalene, 2- chloro-l-(chloromet'hyl)-naphthalene and the like.

The aromatic polyamide fibers as used in the present invention are the fibers consisting of such compounds as represented by the following general Formula 1 or 2.

n1 is 1-12 ml is 30-200 (average polymerization degree) n2 is 1-l2 m2 is 30-200 (average polymerization degree) Referring now to practical operation of the method of the present invention, the dye bath is prepared by emulsifying and dispersing in a stabilized state 3-30 g./l. of one or more of members of alkylbenzene, or alkylnaphthalene whose alkyl moiety being substituted with halogen, or alkylor halogen-nuclear substituted derivatives thereof in a dye bath in which general conditions for dyeing conventional polyamide fibers, for instance, such as nylon 6 and nylon 6.6 with acid dyes are satisfied, and adding thereto a surfactant necessary for emulsifying and dispersing said accelerator in the dye bath in a stabilized state. Into the thus prepared dye bath, aromatic polyamide fibers are dipped and treated at a temperature within a temperature range of about C. and below 130 C. for more than 30 minutes and within 180 minutes, preferably for about minutes, whereby the dyes are rapidly diffused into the fibers by the action of the aforesaid compounds being present in the dye bath.

The method of the present invention can also be carried out by previously emulsifying and dispersing in a bath more than 10 g./l. of the aforesaid accelerator and a surfactant necessary for emulsifying and dispersing said accelerator into the bath in a stabilized state, and then dipping the fibers into said bath to pretreat at a temperature within a temperature range of above 80 C. and below C. for 30 minutes, then the dyeing is carried out under the conditions in accordance with conventionally general dyeing method.

When the amount of accelerator to be added to a dye bath is less than the aforesaid range, the effect thereof becomes poor, and when it exceeds the aforesaid range, not only no increase in its effect in proportion to an increase in the amount used can be expected but also dyeability of the fibers is hindered. Furthermore, in case an accelerator is added to a pretreatment bath, the highest effect can be obtained at the amount of more than 10 g./l.

According to the dyeing method of the present invention, which comprises using a special accelerator, aromatic polyamide fibers can readily be dyed with acid dyes,

metal complex dyes and direct dyes to give a deep shade product, which could not have been dyed with dyes other than disperse dyes. Among the metal complex dyes, there are included a known class of dyes called Irgalan Dyes which are described in the article The Irgalan Dyes Neutral-dyeing Metal-complex Dyes by G. Schetty in the Journal of the Society of Dyers and Colourists, vol 71, pp. 705724 (1955). In addition thereto, it is possible to obtain a dyed product having brilliancy and wide range of hues, which cannot be obtained in the case of dyeing with disperse dyes.

The following examples are given to illustrate the invention but they are not to be construed as limitation of the scope of the present invention.

EXAMPLE 1 Polyhexamethylene terephthalamide was spun and stretched to obtain staple fibers of 1.5 denier, tenacity of 4.5 g./d. and elongation of 27%. The fibers were dyed in a. dye bath containing 3 g./l. of benzylchloride, 3% O.W.F. of direct dye, Suminol Red RS CI. 23285 (product of Sumitomo Kagakukogyo K.K. CI Acid Red 99) and 1 g./l. of Noigen ES-120 the bath ratio being 1:50 at 100 C. for 90 minutes. The amount of dye absorbed by the fibers was 2.4% O.W.F.

On the other hand, the same fibers as above were dyed according to ordinary method for dyeing nylon 6 with direct dyes, i.e. the dyeing was conducted under the same conditions as above except that 1 g./l. of glacial acetic acid was contained in the aforesaid dye bath in absence of the benzylchloride and Noigen ES-120, and as a result, the amount of dye absorbed of the fibers was 1.0% O.W.F. Noigen ES-120 is a trade name of Daiichi Kogyo Seiyako K.K. for a dispersing agent for dispersing an accelerator assistant in a dyeing bath or pre-treating bath. It comprises oleic ester of polyethylene glycol RCOO (CH CH O H (wherein n is usually 12-50).

EXAMPLE 2 Polyhexamethylene terephthalamide was spun and stretched to obtain staple fibers of 1.5 denier, tenacity of 4.5 g./d. and elongation of 27%. A bath which contains ml./l. of a-chloromethylnaphthalene, 3% O.W.F. of metal complex dyes, Cibalan Yellow-GRL (product of Ciba in Switzerland CI Acid Yellow 116) and 1 g./l. of Noigen ES-l (non-ionic surfactant) and being adjusted to bath ratio of 1:50, was thoroughly stirred to emulsify and disperse sufiiciently a-chloromethylnaphthalene thereinto. Into the dye bath, the aforesaid fibers were dipped and subjected to dyeing at 100 C. for 90 minutes. The amount of dye absorbed was 3% O.W.F.

On the other hand, the same fibers as above were dyed according to ordinary method for dyeing nylon 6 with metal complex dyes, i.e. the dyeing was eifected under the same conditions as above except that 1 g./l. of glacial acetic acid was added to the dye bath in absence of the a-chloromethylnaphthalene and Noigen ES-120, and as a result, the amount of dye absorbed was 1.3% O.W.F.

EXAMPLE 3 Polyhexamethylene terephthalamide was spun and stretched to obtain staple fibers of 1.5 denier, tenacity of 4.5 g./d. and elongation 27%. A bath which contains 3 ml./l. of benzylbromide, 3% O.W.F. of acid dye, Acid Orange II C.I. 15510 (C.I. Acid Orange 7) and 1 g./1. of Noigen ES-120 (non-ionic surfactant) and being adjusted to bath ratio of 1:50, was sufficiently stirred to emulsify and disperse said benzylbromide thereinto, and then the aforesaid fibers were dipped in the dye bath and subjected to dyeing at 100 C. for 90 minutes. The amount of dye absorbed was 1.50% O.W.F.

On the other hand, the same fibers as above were dyed according to ordinary method for dyeing nylon 6 with acid dyes, i.e. the dyeing was conducted under the same 4 conditions as above except that 1 g./l. of glacial acetic acid was added to the aforesaid dye bath in absence of the benzylbromide and Noigen ES120, and as a result, the amount of dye absorbed was 0.6% O.W.F.

EXAMPLE 4 Polyhexamethylene terephthalamide was spun and stretched to obtain staple fibers of 1.5 denier, tenacity of 4.5 g./d. and elongation of 27%. A bath which contains 5 ml./l. of benzalchloride, 3% O.W.F. of direct dye, Suminol Red RS CI. 23285 (product of Sumitomo Kagakukogyo K.K. CI Acid Red 99) and 1 g./l. of Noigen ES-120 (non-ionic surfactant) and being adjusted to bath ratio of 1:50 was thoroughly stirred to emulsify and disperse said benzalchloride thereinto. Thereafter, the aforesaid fibers were dipped into the dye bath and subjected to dyeing at 100 for minutes. The amount of dye absorbed was 2.8% O.W.F.

The same fibers as above were dyed according to ordinary method of dyeing polyamide fibers with direct dyes, i.e. the dyeing was carried out under the same conditions as above except that 1 g./l. of glacial acetic acid was added to the aforesaid dye bath in absence of the benzalchloride and Noigen ES120. The amount of dye absorbed was 1.4% O.W.F.

EXAMPLE 5 Poly-p-xylyleneadiparnide was spun and stretched to obtain fibers of tenacity of 3.5 g./d. and elongation 27%. A bath which contains 10 mL/l. of benzylchloride, 30% O.W.F. of direct dye, Kayarus Supra Gray VGN C.I. 25040 (Cl. Direct Black 71) and 1 g./l. of Noigen ES- 120 and being adjusted to bath ratio of 1:50 was thoroughly stirred to emulsify and disperse sufficiently said benzylchloride thereinto. Thereafter, the fibers were dipped into the dye bath and subjected to dyeing at C. for 90 minutes. The amount of dye absorbed was 1% O.W.F.

The same fibers as above were dyed according to ordinary method of dyeing nylon 6 with direct dye, i.e. the dyeing was carried out under the same conditions as above except that 1 g./l. of glacial acetic acid was added to the aforesaid dye bath in absence of the benzylchloride and Noigen ES-l20. As a result, the fibers were just dyed no more than stain.

EXAMPLE 6 Polynonamethylene terephthalamide was spun and stretched to obtain fibers of tenacity of 3.53.9 g./d. and elongation of 27%. A bath which contains 10 mL/l. of benzylbromide, 3 O.W.F. of metal complex dye, Irgalan Green BLS (product of Geigy in Switzerland) and 1 g./l. of Noigen ES- and being adjusted to bath ratio of 1:50 was stirred thoroughly to emulsify and disperse said benzylbromide thereinto. Thereafter, the aforesaid fibers were dipped in the dye bath and subjected to dyeing at 100 C. for 90 minutes. The amount of dye absorbed was 2.7% O.W.F.

The same fibers as above were dyed according to usual method of dyeing nylon 6 with metal complex dyes, i.e. the dyeing was conducted under the same conditions as above except that 1 -g./l. of glacial acetic acid was added to the dye bath in absence of the benzylchloride and Noigen ES-120. The amount of dye absorbed was 0.1% O.W.F.

EXAMPLE 7 Polydecamethylene terephthalamide was spun and stretched to obtain fibers of tenacity of 2.5-3.7 g./d. and elongation of 27-40%. A bath which contains 10 rnl./l of benzylchloride, 3% O.W.F. of metal complex dye, Irgalan Green BLS and 1 g./l. of Noigen ES-120 and being adjusted to bath ratio of 1:50 was thoroughly stirred to emulsify and disperse said benzylchloride thereinto. Thereafter, the aforesaid fiber was dipped in the dye bath and subjected to dyeing at 100 C. for 90 minutes. The amount of dye absorbed was 2.3% O.W.F.

The same fibers as above were dyed according to usual method of dyeing nylon 6 with metal complex dyes, i.e. the dyeing was effected under the same conditions as above except that 1 g./l. of glacial acetic acid was added to the aforesaid dye bath in absence of the benzylchloride and Noigen ES-120. The amount of dye absorbed was 0.1% O.W.F.

EXAMPLE 8 Polyhexamethylene terephthalamide was spun and stretched to obtain fibers of 1.5 denier, tenacity of 4.5 g./d. and elongation of 27%. A bath which contains 5 ml./l. of a-chloromethylnaphthalene, 3% O.W.F. of metal complex dye, Irgalan Green BLS and 1 g./l. of Noigen ES-l20 and being adjusted to bath ratio of 1:50 was thoroughly stirred to emulsify and disperse said a-ChlOI'O- methylnaphthalene thereinto. The aforesaid fibers were dipped into the dye bath and subjected to dyeing at 100 C. for 90 minutes. The amount of dye absorbed was 2.8% O.W.F.

The same fibers as above were dyed according to usual method of dyeing nylon 6 with metal complex dyes, i.e. the dyeing was effected under the same conditions as above except that l g./l. of glacial acetic acid was added to the aforesaid dye bath in absence of the benzylbromide and Noigen ES-l20. The amount of dye absorbed was 0.8% O.W.F.

EXAMPLE 9 Tow of polyhexamethylene terephthalamide as used in Example 1 were dipped in an emulsion bath containing 15 mL/l. of benzylbromide and 1 g./l. of Noigen 135-120 at 80 C. for 30 minutes. The fibers were taken out of the bath and dipped into a bath containing 3% O.W.F. of metal complex dye, Irgalan Green BLS and being adjusted to bath ratio of 1:50 and subjected to dyeing at 100 C. for 90 minutes. The amount of dye absorbed was 2.7% O.W.F.

What is claimed is:

1. In a process for dyeing aromatic polyamide fibers with dyes in a dyebath, an improvement comprising adding an accelerator in a range from 3-30 g./l. to the dye bath, said accelerator being at least one member selected from the group consisting of benzylchloride, benzylbromide, benzalchloride, benzalbromide, benzotrichloride, benzotribrornide, a-chloroethylbenzene, fi-chloroethylbenzene, u-bromoethylbenzene, ,B-bromoethylbenzene, o-, mand p-methylbenzylchloride, o-, mand p-chlorobenzyldichloride, o-, mand p-bromobenzylchloride, o-, mand p-methylbenzylchloride, o-, mand p-chlorobenzylbromide, o-, mand p-bromobenzylbromide, 1- and 2- (chloromethyl) -naphthalene, 2- dichloromethyl) -naphthalene, l-(fl-chloroethyl) naphthalene, 1- and 2-(bromoethyl)- naphthalene, l-(a-bromomethyl)-naphthalene, land 2- (fl-bromoethyl)-naphthalene, Z-methyl-1-(chloromethy1)- naphthalene and 2-chloro-1-(chloromethyl)-naphthalene.

2. In a process for dyeing aromatic polyamide fibers with dyes, an improvement which comprises pretreating said fibers in a bath containing an accelerator, the concentration of which is from 10 g./l. to 30 -g./l., the said accelerator being composed of at least one member selected from the group consisting of alkylbenzenes and alkylnaphthalenes in which at least one of the hydrogen atoms of the alkyl moiety is substituted with a halogen, and derivatives thereof in which the aromatic ring is substituted with an alkyl group or halogen atoms, and then dyeing the pretreated fibers.

3. A process according to claim 1, wherein the dyes are selected from the group consisting of direct dyes, acid dyes and metal complex dyes.

4-. A process according to claim 2, wherein the dyes are selected from the group consisting of direct dyes, acid dyes and metal complex dyes.

5. A process according to claim 1, wherein the accelerator is added in emulsified form.

6. A process according to claim 2, wherein the accelerator is added in emulsified form.

7. A process according to claim 1, wherein the aromatic polyamide fibers are composed of aromatic compounds represented by the following general formula wherein n1 is 1-12, and m1 is average polymerization degree of 30-200, or

{NH-cHZ-QoHZNHGOO- Cm) nr-oooj wherein n2 is 1-12, and m2 is average polymerization degree of 30-200.

8. A process according to claim 2, wherein the aromatic polyamide fibers are composed of aromatic compounds represented by the following general formula wherein n1 is 1-12, and ml is average polymerization degree of 30-200, or

References Cited UNITED STATES PATENTS 1,803,008 4/ 1931 Ellis ct a1. 8-94X 2,274,751 3/1942 Sowter et a1. 8-94 2,828,180 3/1958 Sertorio 8-55DX 3,380,969 4/1968 Hill et a1. 260-78 OTHER REFERENCES B. Sprague et al., Textile Research Journal, vol. 35, November 1965, pp. 999-1008.

Ex parte Schoeneberg et al., decision of the Board of Appeals, Patent No. 3,190,718, Paper No. 27, 4 pages.

Ex parte Schoonover et al., decision of the Board of Appeals, Patent No. 2,743,991, Paper No. 23, 6 pages.

GEORGE F. LESMES, Primary Examiner T. J. HERBERT, IR., Assistant Examiner US. Cl. X.R. 8-94, 178 

